Means for filtering oil in the lubricating system of an internal-combustion engine



July 27, 1926. 1,594,335

E. J. SWEETLAND MEANS FOR FILTERING OIL IN THE LUBRICATING SYSTEM OF AN INTERNAL COMBUSTION ENGINE Original Filed June 5, 1920 Patented July 1926.: i

PATEN r OFFICE.

ERNEST J. SWEETIAAND OF'HAZLETON, PENNSYLVANIA.

MEANS FOR FILTERING OIL IN THE LUBRICATING SYSTEM OF AN INTERNAL-COM- BUSTION ENGINE.

Continuation of application Serial so. 893,807, filed June a, 1920. This application lust. April 1926, Serial No. 105,891. a

The invention relates to a filter for clarifying the oil in lubricating systems of internal combustion engines and is particularly adapted for use in connection with the internal combustion engines of motor vehiclesutmost importance in order to insure the of ficient operation of the engine as well as the long life of the moving parts thereof, as the presence at such matter in the oil. even though in -.rna1l quantities, will cause the engine to operate in a less etlicient man'- ner, and will eventually result in causing wear of the moving parts, thus necessitating the repairing or replacing of the same.

According to the usual practice the lubricating oil is placed within the crank case of the engine and the lubrication of-the engine during its operation is accomplished either by causing the lower end of the connecting rods'to dip within the oil and splash it over the moving parts, or by withdrawing the oil from the crank case, by a pump or the like, and delivering it directly to the parts requiring lubrication. After the engine has been operated for a length of time, it will be found that the oil is no longer clear but contains certain deleterious matter which is suspended therein. -This deleterious matter may comprise one or more of several substances which have become mixed with the oil during the operation of the engine. The principal substances which are to be found suspended in the oil' after it has been operated for some time, are dust, metallic particles and carbon. The dust or'dirt usually finds its way into the oil by being drawn into the cylinders alon with the air which forms part of the exp osive mixture. The presence of metallic particles in the oil is 'due to the wear of the moving parts, especially if they are not properly lubricated or are not in proper alignment with one an-- other, as in such instances there will be. a

grinding or cuttin action between the parts wh ch results in te separationof particles of the metal. The carbon which. mingles with the oil is due primarily to imperfect combustion of the explosive mixture within the engine cylinders, or to the fact that the gasoline which is used is of a low grade or poor quality. Carbon also results from an inefficlent ignition system, as for example when the spark plugs are fouled, and it also results from oil which has become decomposed by being subjected to a high degree of heat. The carbon thus formed not only affects the operation of the engine by reason of its fouling the spark plugs and valves, and forming a coating upon the cylinder walls and piston, but it also afl'ects the operation of the engine by reason of the fact, that owing to the extreme fineness of the particles, it mixes with the oil with which the piston lubricated and works its way out of the cylinders, between the walls thereof and the pistons, and thus is delivered, along with the oil draining from the cylinders into the body of oil contained within th crank case.

It will thus be seen that within a comparatively short space of time the lubri? eating oil within the crank case becomes charged with dust, dirt, metallic particles and carbon, to such an extent that it becomes unfit for use and must be-removed from the crank case and replaced by clean oil.- This necessitates frequent removal of the oil and is a very material factor in the expense of operating the engine. In order to avoid the necessity of renewing the oil ithas heretofore been the practice to attempt to remove the deleterious matter from the crank case oil, before it is delivered to the parts requiring lubrication, by causing the oil to pass t rough a filter member consisting of wire screening. The use of wire screening as a filter member, however, does not fully accomplish the desired object for although it does serve to remove from the oil large particles of the dust, dirt and metallic particles suspended therein, it does not remove the smaller particles nor does it remove any of the carbon particles as the latter are so till lit)

In accordance with my invention, the crank case oil is freed of all of the sus ended deleterious matter contained therein including the fine particles of carbon, and consequentlythe oil may be used over and over again and need not be w1thdrawn from the crankcase and replaced by clean oil as must be done in the systems now in use, even after the engine has been operated for several months, the crank case oil will be found to be absolutely clear. It IS merely necessary to add oil to the systems from time to time t nsate for the loss of oil due to evapp O Compe a plurality of annular filter elements spaced oration, leakage or the like.

This application is a continuation of my copending application Serial No. 893,807,

filed June 3, 1920.

In the accompanying drawings, forming part of this specification:

Figure 1 is a side elevation of an internal combustion engine showing my filter installed thereon;

Figure 2 is a vertical longitudinalsectional view of the filter shown in Figure 1; and

Figure 3 is a fragmentary sectional view of a modified form of filter.

Referring to the drawings, 1 represents an internal combustion engine of any suitable type having a crank case 2, which contains the oil for lubricating the coacting moving parts of the engine, either by the splash system or by the forced feed system, as above set'forth. Mounted upon the engine, or upon the vehicle frame, is a pump 3, of any approved type provided with an intake pipe 4, extending within the crank case 2 and having its open end positioned adjacent the bottom of the crank case, preferably within a depression 5 formed in the bottom wall thereof. The pump is provided with an outflow pipe 6 leadingto a filter 7 from which the filtered oil is conducted to the crank case bv a pipe 8.

The filter 7 which may be of any suitable construction is shown for purposes of illustration as comprising a casing 9 provided with a removable cover 10 provided with a threaded opening 11 adapted to receive the threaded end of the pipe 6 and with a passage 12 adapted to communicate with the pipe 8 connected to the cover in any suitable manner, as by a coupling 13 screwed upon the end of the pipe 8 and upon a nlpple 14 formed on the cover. The filter is preferably carried by the engine, being secured in position by means of straps 15, as shown in Figure 1. Positioned within the casing 9 and extending axially with respect thereto throughout substantially its length, is a tubular member 16 having a closed inner end and provided with perforations 17 in its wall communicating with the bore 18. The other end of the tubular member extends through an opening 19 formed in the cover 10 and is provided with a shoulder 20 adaptmember is whereby the filter screening ed to engage .the inner wall of the cover. Adjacent its extreme outer end the tubular provided with a thread adapted to receive a nut 21 which engages the. cover 10 and,'together with the shoulder 20, serves to support the tubular member upon the cover. An opening 22 formed in the Wall of the tubular member registers with the inner end of the passage 12 whereby the bore 18 of the tube is in communication with the pipe 8 which leads fromthe filter to the crank case.

Mounted upon the tubular member 16 are from one another b annular spacing members 23, preferably fbrmed of felt or the like, the filter elements and spacing members being securely held in the tubular member by means ofa nut 24 threaded upon the inner end thereof. As shown in Figure 2 each filter element consists of an annular member 25 formed of coarse wire netting, reticulated metal, or the like, enclosed by fine wire screening 26 elements are provided with chambers which communicate with the perforations 17 in the tubular member 16.

The exposed surfaces of the wire screening 26 of each of the filter elements are provided with a coating 27 shown of exaggerated thickness in Figure 2, having the property of preventing the passage therethrough of the fine particles of carbon and other foreign matter which may be suspended within the oil to be filtered, while permitting the clear filtered oil to pass therethrough. This coating consists of a slime bed formed of an insoluble substance and the impurities filtered out. of the oil. The insoluble substance may be kieselguhr, fullers earth, charcoal, carbonate of lime, asbestos in flake .or fibre form, wood pulp, or any other suitable substance which will serve to combine with the suspended deleterious matter in the oil to form a slime bed.

'The insoluble substance may be deposited upon the wire screening in any suitable way. For example, it may be mixed with a vehicle consisting of a liquid or viscous substance and the mixture applied to the screening whereby the insoluble substance will adere thereto, or if desired, the substance, either by itself or mixed with a liquid or viscous substance, may be placed directly within the crank case or within the filter casing, and as the oil to be filtered is caused to circulate the insoluble substance will be carried thereby into engagement with the and deposited thereupon. Moreover the insoluble substance may be applied to the screening either before or after its being formed into filter elements. The in? soluble substance, when deposited upon the screening, serves to collect the finely divided suspended particles from the oil to form assembled position upon vents the passage of any suspended impuritiesbut permitsthe passage of the clear As shown in Figure 2, aivalve 28 of the ytype used in connection "with automobile tires and the like is mounted upon the outer end of the tubular member 16- and communicates withthe bore 18 by means of a passage 29. Upon connecting this valve with a suitable air pump, such as the air pump usually carried by motor vehicles, air may be blown into the bore 18 of the tubular member 16 and through the several filter elements, in the reverse directionfrom the flow of oil through the filter, and this air will tend to remove the slime bed from the filter elements when cleaning of the-same is necessary or desirable. The air thus forced into the filter casin escapes through a suitable normally close petcock 30 communicating with the interior of the filter casing.

During the o eration of the engine, the pump 3 will withdraw oil from the crank case 2 through the pipe 4 and force it through the pipe 6 into the casing 9 of the filter 7, and into engagement with the several filter elements mounted upon the tubular member 16. The deleterious matter which may be suspended in the oil, including the extremely fine carbon particles, cannot pass through the slime bed 27 and will therefore be extracted from the oil, and the clear oil, free from all impurities, will be forced through the slime bed 27 and wire ducts it back to the crank case 2.

Referring to Fi ure 3, there is shown a filter, the filter 'ements of which differ slightly in construction from the ones shown in Figure 2. In the modified form each filter element consists of an annular member 31 formed of wire netting reticulated metal or the like enclosed by a closewovcn cloth fabric 32 such as duck, canvas, chain-cloth or the like, having an extremely fine mesh which will serve to collect the finest particles suspended in the oil to be filtered. In use, at the commencement of the filtering operation a portion of the fine suspended particles will pass through the fabric 32, but within a short time the impurities collected thereon will serve to prevent the passage therethrough of any of the fine particles with the result that only the clear oil freed from all suspended matter will pass through the fabric. It is of course understood that a coating or slime bed, as above described, may be non-metallic fabric 32 if mama-althou h I have found that such fabric without the coating will operate in a satisfactory manner. The fabric may be provided with strands of wire to increase its strength, if desired.

While I have described my filtrate-as being clear or free from visible solids, it will be understood that the primary purpose of the invention is to remove solid particles of asize which would cause a break in the .oil film between the bearings or would cause abrasion of the moving, parts, and that solid particles of a microscopic size or of smaller size than the normal thickness of the oil film between the bearing may be permitted to remain in the oil without departing from the purpose or spirit of my invention.

' Although the passage of the filtered oil and the like have been known heretofore, in

which, however, the size of the filter necessary to filter the engine oil with suificient rapidity to keep it clean, was much too large to be carried as an accessory on an automobile. Filters have also been known which were designed to be carried on the automobile engine, but in which the effective filtering area if of sufiiciently fine mesh to accomplish filtration, was much too small to filter the crank case oil at a sufficiently rapid rate to effect any substantial clarification of the oil, and where in these latter filters, screens or coarse mesh material are used through which the oil may flow without retardation, no useful result is accomplished. It will be readily apparent that a filter of the hitherto known type if able to filter the contents of a normal crank case once every hour of engine operation must be as large. or larger than the automobile engine itself as if the filter were made of sufliciently small size to be carried on the engine, it could filter only a few ounces of oil per day and would be ineffective for my purpose. The two types of filters heretofore known are equally ineffective, the former because of its prohibitive size and the latter because the filtration of a few ounces of oil in the crank case will never clarify the entire contents or remove the impurities as rapidly as they are added by the operation of the engine.

My invention which provides a large filformed in any suitable manner upon the tering area, large enough to filter the entire contents of the crank case once in every hour of engine operation, or more often and remove the impurities at a more rapid rate than they are formed, and yet enclosed in a casing of sufliciently small size to be carried on the engine provides a novel solution to both these problems and the ada ting of the size of the casing to the size 0 the engine and the filter area to both the permissible size of the casing and the contents of the crank case, and the pump ies'sure so as to provide a definite rate of ltratio n as compared to the engine operation is a new idea in regard to filters.

It is of course understood that I do not limit my invention to the specific embodiment shown, but that I intend to cover the same broadly in whatever form its-principle may be employed. i

What I claim as my invention is:

1. A pressurefilter for use in the lubricating system ,of an automotive internal combustion engine comprising a caslng capable of being received and supported beneath the hood of the engine and a filter element therein designed to repeatedly filter the predetermined normal oil content of the system within a given time, modified from previous practice for the same quantity of oil under treatment by a substantial increase in effective filtering area and a substantial decrease in ratio of thickness of element to extensiveness of said area-so as to permit of the compact arrangement of the element within the casing, the effective areabeing of sufli- -cient density to substantally free theoil in the system of deleterious solids. v

2. A pressure filter for use in the lubricating system of an automotive internal combustion engine comprising a casing capable of being received and supported beneath the.

engine hood, and a filter element therein designed to repeatedly filter the predetermined normal oil content of the system within a given time, modified from previous practice for the same quantity of 'oil to be treated by a substantial increase in efi'ective filterlng area and a substantial decrease in ratio of thickness of element to extensiveness of said area so as to permit of an arrangement of the element in plural juxtaposed portions within the casing and the effective area being of suflicient density to maintain the oil substantially free of deleterious solids.

3. An oil filter for use in the lubricating system of an automotive internalcombustion engine, comprising'a filter casing of small size, mounted on the vehicle, a filter surface therein of sufliclent density to permit the seepage of the 'oil theretltrough, said" filter surfacebein of sufficiently large area I to filter out, in t e aggregate a sufficient 1 amount of deleterious solids in a given period of time to prevent the accumulation of such deleterious solids in the oil and said seepage of the oil through each portion of said large area permitting only a slow accarried as an accessory on an automobile,

inlet and outlet openings to said casing from the lubricating system, a filter surface in said casing of relatively fine mesh fabric,

which ofiFers. a resistance to the passage of oil therethrough, necessitating a pressure in excess of gravity to efi'ect filtration, said filter surface being or relatively large area as compared with the size of said casing whereby all of the oil in said lubricating system may be filtered with suflicient frequency'at normal oil pressures to maintain the oil substantially free of deleterious solids.

5, A pressure filter for use in the lubricating system of an automotive internal combustion engine comprising a casing capable of being received and supported beneath the hood of the engine and a filter element therein designed to repeatedly filter the pre' determined normal oil content of the system within a given time, modified from previous practice for the same quantity of oil under treatment by a substantial increase in effective filtering area and a substantial decrease in ratio of thickness of elementto extensiveness of said area so as to permit of the compactarrangement of the element within the casing, the effective area being of sufficient density to collect a carbonaceous slime bed wherebyithe oil in the system is freed of deleterious solids at a rateequal to at least the maximum rate of contamination of the oil during the operation of the engine.

' In testimony whereof I have afiixed my signature to this specification.

ERNEST J. SWEETLAND 

